1. Field of the Invention
The present invention relates to a method and to apparatus for cooling strip and wire material.
2. Description of the Related Art
In the manufacture of strip and wire material, the material is normally annealed after being finally rolled or drawn, respectively. In the case of stainless steel, a typical annealing temperature is 900-1200° C., and the product is annealed continuously after being worked. This follows with controlled cooling of the product to a typical temperature of 20-50° C. below the oxidation temperature.
In normal operation, the wire or strip speed may be about 1 m/s. Because the cooling process will necessarily take a given amount of time to carry out, it is necessary that the path along which the cooling process takes place is relatively long.
According to earlier techniques, the cooling path is essentially straight, among other reasons because the annealed material is extremely sensitive to plastic deformation and therewith easily damaged when passing through curved cooling paths. In turn, this means that the building which houses the cooling path must be very long, for instance in the order of 10 meters or more. Moreover, when cooling wire or strip, it is necessary to handle a long wire rod that is used to thread the product through the cooling path to a coiling plant.
Thus, it is desirable to be able to reduce the length of the cooling path and thereby reduce the space required to accommodate said path, and also to reduce the smallest necessary length of said path required by the wire rod used to lead the product through the furnace and the cooling path and up to the coiling plant. The furnace and the cooling path are joined together.